The engine immobiliser system is designed to prevent the vehicle from being stolen. This system uses a transponder key ecu that stores the key codes of authorized ignition keys. If an attempt is made to start the engine using an unauthorized key, the ecu sends a signal to the ecm to prohibit fuel delivery and ignition, effectively disabling the engine.

The transponder key coil receives this signal, the transponder key amplifier amplifies it, and then the signal is transmitted to the ecu. The ecu matches the key's id code with the vehicle's id code, which was previously registered in the ecu and then communicates the results to the ecm using sfi communication.
Engine immobiliser system
How to proceed with troubleshootingCan communication system
Precaution
Precaution
Turn the ignition switch off before measuring the
resistance of the main wire and the branch wire.
After the ignition switch is turned off, check that the
key reminder warning system and light reminder
warning system are not in operation.
Before measuring th ...
System description
General
This system has the following functions: manual slide
open and close; auto slide open and close; manual tilt up
and down; auto tilt up and down; jam protection; and key
off operation.
Function of main component
System operation
The sliding roof has the following ...
Only passenger door lock / unlock functions do not operate
Description
The main body ecu receives lock / unlock switch signals and activates the
door lock motor accordingly.
Wiring diagram
Inspection procedure
Read value of intelligent tester (lock position switch)
Use the data list to check if the door lock is
functioning properly.
...